SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bfbdf30ed06212d08ad8703ab0ae7cab280b6db40c137756cff26456c8002064' 
  AND token = 'yJnLb7XOJVdbsKZNUQq/MujCy5yZDp+wclScTs5/g7Q=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}